The present invention relates to a rolling guide device in which a block and a rail are relatively linearly movably engaged to each other via rows of infinitely circulating rolling members, a manufacturing method thereof, and a driving device including the rolling guide device.
Heretofore, there has been known a rolling guide device in which a block and a rail are linearly movably engaged to each other via a plurality of rolling members comprising infinitely circulating balls and rollers. To be specific, as shown in FIG. 8, the rolling guide device comprises a rail 80, a block 90 having a recess 93 formed on a lower surface thereof in which the rail 80 fits, and a number of rolling members 100 interposed so as to form a row between a rolling member rolling surface 81 of the rail 80 and a loaded rolling member rolling surface 91 of the block 90.
Here, the block 90 is provided with rolling member release holes 94 through which the rolling members 100 passed between each pair of the rolling member rolling surface 81 and the loaded rolling member rolling surface 91 are released and returned to an original position again to from an infinite circulation passage of the rolling members 100.
Furthermore, when the block 90 is linearly moved relatively along the rail 80, the rolling member's 100 are linearly moved while they roll between the rolling member rolling surface 81 and the loaded rolling member rolling surface 91, passed between the rolling member rolling surface 81 and the loaded rolling ember rolling surface 91, returned to the rolling member release hole 94 through a return passage provided in an end plate (not shown), and then supplied again between the rolling member rolling surface 81 and the loaded rolling member rolling surface 91.
However, for example, in the case that the block 90 is fixed and the rail 80 is moved in the aforesaid rolling guide device, and when a heavy piece is installed at a rail tip portion of the forward side of the rail 80 in FIG. 8 and a moment load is applied thereonto, the load imparts an uneven deformation onto the block 90, so that a deformation amount (an opening amount of the recess 93) is varied on the forward side and the backward side of the block 90 in FIG. 8, which leads to a problem that the position accuracy of the rail 80 is impaired.
In order to solve this problem, instead of the recess 93, a through hole may be provided at the center of the block 90 to pass the rail 80 through the inside of the through hole. If constituted in this manner, even in the case that an uneven load is applied onto one side of the rail 80 and the moment load is generated, the recess 93 will not be opened, so that the rail 80 can always securely be held.
However, even in the rolling guide device constituted in such a manner, machining positions of the opposing rolling member rolling surface 81 and the loaded rolling member rolling surface 91 are required to be changed to various positions (various contact angle positions) in accordance with purposes of use, and hence, the shape of an opening 25 of the block 90 and the external shape of the rail 80 must also be changed in accordance with the above change, thereby causing a complicated problem.